Question

In a glass sphere, there is a small bubble 22 x 10${}^{-2}$m from its centre. If the bubble is viewed along a diameter of the sphere, from the side on which it lies. The distance from the surface where it appears is
(The radius of glass sphere is 25 x 10${}^{-2}$m and refractive index of glass is 1.5)

• A. 22.5 x 10 ${}^{-2}$m
• B. 23.2 x 10${}^{-2}$m
• C. 26.5 x 10${}^{-2}$m
• D. 20.2 x 10${}^{-2}$m

Answer 1

Answer: (A)

22.5 x 10 ${}^{-2}$m

$x=22\times {10}^{-2}m$

$R=25\times {10}^{-2}m$

$\frac{{\mu }_2}{v}-\frac{{\mu }_1}{u}=\frac{{\mu }_2-{\mu }_1}{R}$

$\frac{1}{v}+\frac{3}{2\times 3}=\frac{1}{2\times 25}$

$\frac{1}{v}=\frac{2}{100}-\frac{50}{100}$

$\frac{1}{v}=\frac{48}{100}$

$v=\frac{50}{24}=\frac{25}{12}$

$d=25-\frac{25}{12}=22.5cm$